With less than two weeks to go until the elections, the presidential race continues to revert to the norm, a development that can only worry the president and his top strategists.

States that historically have been competitive in presidential elections or tilted to the GOP are moving in that direction, even though just a month ago they were favoring Barack Obama.

Yes, it is still easier to see the president’s route to 270 electoral votes than it is to see Mitt Romney’s, but the momentum in this race is now all with the challenger. No sensible person ought to be confident that he or she knows who will win.

No matter who emerges victorious next month, the first presidential debate of 2012 is now certain to go down in history as the same kind of game changer that the 1980 debate between Ronald Reagan and Jimmy Carter was.

After spending the summer defining and discrediting Romney in key states and nationally, the Obama campaign now finds itself facing an opponent who, in just 90 minutes, erased much of the image that David Axelrod and David Plouffe created in a series of negative ads over the summer.

Romney’s new image and positioning in the race — moderate, reasonable and focused on problem-solving — make him a far more acceptable alternative than he once was, and that has made it easier for voters to focus their attention during the final month of the campaign on the president and his record, which remains mixed.

Obama’s better performances during the second and third debates did not change the fact that the first debate fundamentally altered voters’ opinions of the challenger.

Many of the reactions to the third debate by serious journalists and Democratic cheerleaders totally missed the point. (But Dana Milbank’s clever and on-target column in the Washington Post about real-time tweets during the debate is a must-read.)

Liberals and Democrats saw what they wanted to see Monday night, a classic danger for anyone trying to evaluate the debate’s effect on voters.

“Romney looked pained and rambling through most of the debate. I don’t think I’ve ever seen Romney sweat like that, literally or figuratively,” Talking Points Memo’s Josh Marshall wrote in proclaiming the president the clear winner.

“President Obama won the foreign policy debate, cleanly and decisively, on both style and substance. It was as clear a victory as Mitt Romney’s in the first debate,” Time magazine’s Joe Klein wrote.

Romney “didn’t have a single creative or elegantly stated foreign policy thought and, indeed, seemed foolish at times,” Klein asserted, adding that “Obama didn’t have a single weak or unconvincing moment.”

But mainstream reporters also seemed off the mark in evaluating the two candidates’ performances.

In labeling Romney a “loser” in the debate, the Washington Post’s Chris Cillizza wrote the former Massachusetts governor “struggled to differentiate how his foreign policy would differ from what Obama has pursued over the past four years.”

My own reaction on Monday night to the question of who won the debate was very different: Ask me in a few days, after a handful of reliable surveys show how the public evaluates the candidates. Then I’ll have some idea who won.

Yes, the president probably “won” the debate on points if a debating society scored the result.

But political debates aren’t academic exercises where students receive good grades for performing the way their textbooks or professors say they should. And they aren’t high school wrestling matches where the aggressor scores points and automatically wins the match.

Debates are about improving a candidate’s chances of winning an election, and it was far from clear on Monday evening how, or whether, the debate would affect voters’ intentions.

For example, I’m skeptical that Romney needed to “differentiate” himself from the president on foreign policy. If Romney wins the election, it is likely to be because of the economy, not foreign policy.

If that is true, he simply needed to demonstrate to voters — not to Joe Klein — that he could handle national security and defense issues capably, much as Reagan had to do in 1980.

Polling immediately after the debate certainly wasn’t decisive, and “quickie” polls should always be viewed skeptically, as should any survey results gathered during or immediately after a major event.

Still, it’s clear that since the first week in October, both the national polls and swing-state polls have shown Romney’s percentage of the vote growing and the president’s slipping. The national polls are about even.

This week, I went back to the 2004 and 2008 results in the key states to see where Obama and George W. Bush outperformed their national numbers and where they underperformed. I also looked at how strongly they outperformed or underperformed. The results are interesting, though I don’t suggest they are predictive.

Obama did not do as well in Virginia, Florida and North Carolina as he did nationally (in terms of his margin of victory, according to CQ Press’ America Votes 2007-2008), while Bush had a larger margin in the three states than he did nationally over John Kerry (D).

Obama won nationally in 2008 by 7.2 points, but he carried Virginia by 6.3 points, Florida by only 2.8 points and North Carolina by just three-tenths of a point. Yes, he carried all three, but his margins were worse than his national margin.

Similarly Bush won re-election in 2004 by 2.4 points, but he carried Virginia by 8.2 points, Florida by 5 points and North Carolina by 12.4 points.

On the other hand, Obama outperformed in Iowa, Wisconsin and New Hampshire, while Bush did worse in all three than he did nationally. Obama carried Iowa by 9.5 points, Wisconsin by 13.9 points and New Hampshire by 9.6 points. Bush lost all three states, albeit very narrowly.

Assuming the presidential race is a squeaker nationally and the six states just mentioned outperform and underperform in the same directions they have in the past, Obama would be at 257 electoral votes to Romney’s 248, with three states — Colorado, Nevada and Ohio — and 33 electoral votes remaining.

Obama outperformed in Colorado, carrying it by 9 points, but Bush outperformed there, as well, winning it by 4.7 points during his 2.4-point national victory. Obama also outperformed in Nevada (carrying it by 12.4 points), but Bush outperformed (very narrowly) as well, winning it by 2.6 points.

Ohio underperformed very slightly for Bush in 2004 (who carried it by 2.1 points), while Obama also underperformed in the state, winning it by only 4.6 points. It was the only swing state that underperformed for both men.

In the final 10 days, swing voters certainly could collectively make a decision to rehire the president or to fire him. But at this point, it seems more likely that we are headed to a tight and possibly inconclusive election night.